Machine gun



Nov. 1.4, 1944. v. A. BRowNlNG MACHINE GUN Filed Ocl..` 29, 1940 3 Sheets-Sheet 1 v. A. BRowNxNG- 2,362,63

MACHINE GUN Filed oct. 29, 1940 3 sheets-sheet 2 Nov. 14, 1944. v A, BROWNING 2,362,613

MACHINE GUN Filed oet. 29, 1940 5 sheets-Sheet 3 LAROWNWG Patented Nov. 14, 1944 Val A.:Browning,.0gden, Utah, assigner to.k 1.1M. & M. S. Browning Company, ,0gden,1Utah,.a

corporationrof `Utah AipDlicaIiIl 0ctoi'er`29, 1940, Serial No. 363,263

`- Claims.

The present invention relates to automatic machiney guns and more particularly to machine gurisfof the recoil operated, beltfeed type.

The object of the present invention is to provide a gun ofl the above-indicateditype wherein the barrel structure may be readily and `quickly mounted anddismounted from the breech casing. The advantage of'such a structure is vthat air cooling means may be utilized in conjunction with the barrel, thus eliminating the watercooling means which heretoforehave been necessary in guns of the recoil operated type. 1A11-- other advantage is that. thegun may be properly breeched without stripping any' of the breechcasing.

Another object is toprovide a barrel structure incorporating' latching means which are automatically operable upon the mounting of the barrel structure upon the breech casing' tormly secure the parts in proper alignedpositon.

Other objects will be in part obviousand in part pointed out more in detail hereinafter.

The invention accordingly consists `inthe features of construction, combination ofelements, and arrangement of parts which willbeexemplined in the construction hereafter. set forthand the scope of the application of' which. will be im dicated in the appended claims.

In the accompanying drawings:

-Figure l is a view of a completely assembled machine gun embodying the invention herein;

Fig. 2 is'a view partly in section showing the interconnecting and interlocking means between the barrel structure and the breech casing;

Fig. 3" is a plan view' partly in section showing details of construction of the connecting means;

Fig. 4 is'a partial sectional view 'of the breech casing with the barrel structure being assembled therein; i

Fig. 5 is a perspective view ofthe forward end of the breechl casing withthe side plates broken away to show the forward end of the barrelextension;

Fig. 6` is a perspective viewshowing end of the breech casing;

Fig. 7 is aperspective view oi the interlocking end of the barrel structure; and

Fig. 8' is a perspective view similar .to Fig. 7, but showing another type of barrel structure.

` Referring to the drawings, the invention coniprises generally an automatic machine gun having a receiver or breech casing I0, a barrel structure Il comprising a barrel support 2 andlbarrell I`4`V `carriedl thereby, and latching .means |45 for securing the removable barrel 4structure,oni'zothe the forward breech casing HI. The gun is of the type wherein thebarrel recoils upon nring of the gun, and the recoil action is utiiized to operate the firing, ejecting', and feed mechanism. For purposes of simplcity, no showing Vof the firing, ejecting, and feed mechanism wil be shown, other than such parts as are required for an understanding of the invention herein.

More specically, the breech casing In includes the usual side plates I6 having secured between their forward ends a trunnion block I8 so positioned that itsfforward face Ztl` is rearwardly of but parallel to Vthe Aforward edges of the side plates i6. Intermediate. of the trunnion block face 20 and the-forward edges of the side plates t6. the inner walls ofthe latter are cut to provide opposed vertically extending mortlces 22 for positioning and interlocking the barrel support I2 to the breech casingV II), as is hereinafter apparent.

x As in previous recoil operated machine gun structures, there is also slidably mounted in the breech casing a barrel extension 24. Herein the side arms 26 ofthe barrel extension are joined attheir forward upper edges by a cross plate 28 and' are open between their lower forward edges. The inner walls of the side arms 26 and the cross plate. 28 are machined to an inverted vU` shape Vsee Fig; 5*) and inwardly from the forward edges the side walls arecut AtoV provide opposed vertically; extending mort'ices 3U for positioning and interlocking the barrel, as is` hereinafter apparent.

Referring now to the barrel support I2, it includes a rear barrel receiving member comprising a rectangular block 32 and a forward barrel receiving member comprising a rectangular block interconnected by parallel side plates 3s. To

` interconnect the barrel support I I on the receiver IILthe rear side edges of' the supporting member 32 are provided with laterally projecting, vertically extending tenonsss adapted, upon proper alignment ofthe barrel support and receiver IU, to be telescoped within the receiver mortices 22 for interlocking .the parts together. As indicated, the barrel ,[4 iscarried by the barrel support I and mounted inalignedbores 42 provided in the front and rear Vblocks 34 and 32. The barrel ,isi furtherprovidedwith a stop member 44 for limiting its movementrelative to the support before being mounted onto the receiver. Aswpreviously indicated, `air cooling means can be used with the lbarrel ofthe gun shown therein, and theseaircoolng means may be of the type shownV in the copending. application Serial No. 363.262 ,tothesance` inventor. iiled` on even date has threadably mounted thereon a barrel con.

nector 5D for connecting it with the barrel ex- 4 tension 24. The barrel'` connector 5l)` comprises an elongated block machined to Aconform to the inverted U shape of the forward end of the barrel extension 24, whereby it will make a snug fit therewith when positioned in same. l and interlock the connector 50 within the barrel extension, the connector adjacent its rear end is provided with laterally, vertically extending tenons 52 receivable within the barrel extension mortices 30.

With the above construction it will be seen that upon telescoping the barrel support Il into'the'y breech casing l0 from the bottom thereof the barrel connector 50 will likewisev be telescoped into the barrel extension 24, thereby interlocking and positioning the partsagainst any movement relative to one another except in the downward direction for disassembly, As best seen in Fig.` 3, when the parts are so-assembled the trunnion face 20 and the rear face 40 of the barrel support member 32. are in closely abutting relationship with the barrel support H in rigid alignment.

To facilitate the assembly, the inner walls of the breech casing side plates I6 may have secured thereto oppositely disposed camming members 54 *bore To position f .6l C.

upper krear .corner 65 has a bore, and the stem 63 extends diametrieauy through the bolt adjacent the rear end of the The stem is pivoted to the bolt by a pin The block 32, comprising the rear barrel receiving member of the barrel support, has a circumferential slot 65 through which the stem 4 631s adapted to extend, and when this stem is in the vertical position shown in Fig. l and the bolt isin :its rear or latching position, the rear edge of the stem contacts with, or lies closely adjacent to, the rear face of the slot 65. The between the ,rear face of the slot and the top surfacev of the member. 32

' constitutes a fulcrum point or edge about which and receiver lgvheld 'f which slant downwardly and yrearwardly from the barrel extension mortices 30. The lower front edges of the camming members 54 are positioned rearwardly of the mortices a slightly greater distance than the permissible relative movement between thebarrelstop 44 and the barrel supporting member 32, whereby if the barrel should be in its rearmost position upon alignment of the barrel support and breech casing,

the barrel connector will engage the cams and be moved forwardly and into proper alignment with the barrel extension mortices 30 See Fig. 4).

It is obvious from the foregoing that withv this construction the barrel support and barrel may be readily assembled With the breech casing and barrel extension without stripping any of the breechv mechanism. The use of a separate connector also reduces manufacturing diiiiculties as it isV not necessary to accurately machine the cartridge receiving end-,of the barrel to breech the gun; the breeching being accomplished lby merely rotating the barrel in the connector 50. Moreover, this construction makes it possible to breech the gun without stripping any of the mechanism, for eveny with the parts assembled the barrel I4 may be rotated within the lconnectorA 50 and, when properly breeched, the barrel may be secured by any suitable means, such as a set screw carried in thebase of the connector 50 (see Fig. 2).

With the barrel structure assembled onto the breech casing, means must be provided to secure them in assembled position, said means `preferably including means for preventing any relative movement of the parts due to lost motion between the interlocking means. For this'purpose there is utilized a latching means' l5 which not only facilitates assembly, butr is automatically operable upon the parts reaching assembledposition to latch them together and includes means for rigidly holding the parts against any yrelative motion, thus assuring 'accurate alignment at all the operatingmember is adapted topivot as will be hereinafter explained more in detail. The bolt 59 and operatingmember 6I are normally urged to their rearmost position lby a spr-ing 66 having its rear'end positioned against the stem 6| and its front end'against the `base of thebore 62.

When'soy positioned, it will be seen that the yrear orlatching end 68 of.bolt 59 .normally extends beyond the face 40 of the member 32. Tocooperatively receive the projectingor latching end l68 of the bolt,` the face 20 of the tunnion block la is provided with a recess 1u into which the boit end 68 extends to latch the parts together..

In order toprevent any motion of the parts due tok any playbetween the cooperating interlocking members, the spring 66 is sucientl'y long to remain under compression when the parts are latched Iand of suflicient' strength to urge the barrel structureforwardly and take up any play between the" breech casing and barrel structure interlocking means .and prevent any wobb-ing or loose motionfthereof. It ,is evident that other means could be used. Y with the p barrel structure is detached and is not supported by the handle 64, the bolt 'and stem`63 are in the full line position shown in Fig. 7. When Iit is desiredv to assemble the barrel structureto the breech jcasing, the barrel vstructure is lifted .by means of the handle, and when this is doneQthe barrel 'structure tendsl to pivot with respect `,to the stem because the major Weight' of the barrel structure is forwardly of the stem.- During such pivotal movement, the upper rearcorner 65` of thesmt'so eonsntutes'a fulcrum witnthe result After the breech casing is brought into proper` align'ed'position with thebarrel support, the casing `will rest upon the rear end of' thebarrel or the connector50`andjas the breech casing portion fof' the'gun'l now counterbalanoes or slightly overbalancesjthe 1weight `of the barrelhsection forwardlyof the `stem 63, the stemV 63 of the 'op described arrangement, when` the asesora fer-ating( handle will` swing from the .inclined Aposition shown in- Flg. 4 vto thefvcrticallposition shown in Figs. 1 and 2 with the result that the ,bolt will automatically move frornretracted position to `the locking positionv shown in liig. 2. The may now be carried` in its assembled condition by means of the handle 64, the weight orforces being so balanced that the operating member does not-tend to cant with respect tothe barrel sup'port. When it is desired to d-ismount the casing from the barrel structure, it is merely necessary to gripthehandlet with one hand and raise thel breech casing thereby causing the stem 63and the barrel structure to cant relative to. one` another with the result that the bolt is The casing Anow maybe raised out of engagement with the rear end of` the `barrel support. As itis necessary tomovewthe operating member 6I out of the line o'f sight oncethe gun` isassembled, the slot 465 extends-laterally to the outer edge `of the supporting' `member -32 and. downwardly to below the axis of the bolt 59, whereby with thisconstruction thestem Gamay be moved out of alignment by simply turning it through an angle of 90.

In order toassistin the holding of the bolt in either of the aforementioned latching positions as well as to give the operator an indication as to when it is in proper position, the latching end 68 may be provided with semi-circular notches 14 spaced 90 apart. When the stem 63 is in proper vertical position, the top and bottom notches 14 will overle a. semi-circular pin 16 vertically arranged in the latching recess 10. Upon movement of the handle through 90, the bolt will be initially cammed rearwardly sufficiently to clear the top and bottom notches, and when the side notches move to vertical position the bolt spring 6B will again snap the bolt to latching position with the notches overlying the pin 16. When this occurs, a definite click will be heard, thus informing the operator that the handle is in proper position.

` As it is desirable in this type of gun to make all parts readily interchangeable, means are provided for readily removing the bolt from the bolt supporting member 32 when the barrel structure is dismounted. To accomplish this, there is provided a second lateral slot l2 extending from the face 40 of the support 32 to the slot E5. As best seen in Fig. 7, the slot 12 is cut on an angle slanting downwardly from the bolt 59, whereby it lies below the normal position of the operating member (ilr when the latter is moved out of the line of sight for the firing of the gun. To remove the bolt, the stem 63 is simply rotated until it is aligned with the slot l2, whereupon it may be withdrawn rearwardly through the slot. To normally prevent its being moved to such position, there is provided a lug 6l located on the rear Wall of the slot 65 adjacent the base thereof, thus making it necessary to force the stem El slightly against the tension of the bolt spring 66 in order to clear the lug before the stem comes into alignment with the slot l2.

Referring now to Fig. 8, the structure shown therein is generally similar to the barrel structure heretofore disclosed. However, in this embodiment the front and rear barrel supports are of circular cross section to suppot a cylindrical jacket 80. The rear face of the rear barrel support 82 terminates in a rearwardly extending rectangular block 84 provided on its opposite edges with laterally projecting, vertically extendina tenons. I6 "receivable within ythe inortices 22 of the breech casing' l0. Asthe structure vis otherwiseuthe same 'as that shown in the prior embodiment, no further description thereof will ha made.-

. .,.Asmany changes couldbe made in the above `construction'andnnanyA apparently widely different Vembodim ents.or this invention could be made without departing fromthe scopethereof, it .is intended ,that all matter cmitai-ned` in the above. description or shown 'the accompanyall=of the generic'and'specic'featiires of the inventionherein described and .all statements of thescope vofthe invention which, vas a matter oi language, might.` besaid to fall therebetween.

`I claim as my invention:

1. .In a machineguxiofthe recoil-operated-type, a breechcasing, abarrel structure having a barrel support, cooperating mortices and tenons on the forward end of said casing andthe rear end ci' said barrel-support for 'demountably connectmg the. casing 'and barrel supporti a boltY mount- `com the rearend' of said barrel support and having its rear end engageable with said casing when the bolt is in latching position, an operating member connected to said bolt and having a handle by means of which the demounted barrel support may be carried, and means on the barrel support engageable with said operating member for causing retraction of the bolt when the demounted barrel support is carried by the handle due to the overbalancing weight of the barrel structure forwardly of the operating member.

2. In a machine gun of the recoil-operated type, a breech casing, a barrel structure having a barrel support, vertically extending cooperating mortices and tenons on the forward end of said casing and the rear end of said barrel support whereby the casing and support may be demountably connected together by vertically moving one into alignment relative to the other, a bolt mounted in the rear end of said barrel support and having its rear end engageable with said casing when the bolt is in latching position, an operating member connected to said bolt and having a stem upwardly extending through said barrel support and a handle on the outer end of the stem whereby the demounted barrel structure may be carried, and a fulcrum on said barrel structure engageable with said stem and about which said stern pivots to withdraw said bolt to retracted position when the demounted barrel structure is lifted by said handle, said pivotal movement being caused by the weight of the forward end of the barrel structure.

3. In a machine gun of the recoil-operated type, a breech casing, a barrel structure having a barrel support, cooperating mortices and tenons on the forward end of said casing and the rear end of said barrel ``support for demountably connecting the casing and support, a spring pressed bolt mounted in the rear end of said barrel support and having its rear end engageable with said casing when the bolt is in latching position, an operating member pivoted to said bolt and having a handle by means of which the demount- `ed barrel support or the assembled gun may be carried, and means on the barrel support engageable with said operating member for moving the latter to retract the bolt when the demounted barrel support is lifted by the handle due to the 'overbalancing weight .ofthe barrelstructure for'- wardly of the-operating nr'iemb'er.k l- 4.;In a machine gun of the frecoil-operated a bolt reciprocably mounted inthev rear endof said "barrel: support,` the -iorward end oifl said breech casing having an opening adapted to receive the rear `end of said. bolt when the 4latter' is in ylatching position, an; operating member connected to saidbolt and havinga stem extending generally radially outwardly therefrom and -a handle.. on the outer end of the stem whereby the demountablebarrel structure or` the assezn'- bled gun may be carried, and a' fulcrum on said barrel structure engageable with said stem between its ends;and about-which said stem-pivots to withdraw saidv-bolt to retracted positionl when the demounted barrel structure is liftedl by the handle, said pivotal movement being-caused by the weight of the forward endfof the barrel structure, said stein being pivotedabout .saidfulcrum structure. Y

. in 'al :direction to ymove saidbolt to latching position :upon'inounting the casing -on said barrlel 5..In. a machine gun of the recoil-operated .type,la breech casing,a barrel .structure'having a barrel support, cooperating. morticesand tenons on the forward'end vof saidcasing andthe rear endxof said support for demountablyconnecting the casing andbarrel support-together, "a bolt mounted for i recprocation:in"the rear end of: said barrel ,support and having its rear end en'v` gageable with saidlcasing whenv the bolt is `in Alatching position, an4 operating member pivotally i connected to saidubolt and having a handle by-A means of which the demountedbarrel support may. be carried, a Sp'rigxwithinisaid bolt and between. said barrelsupport yand stem, and a fulcrumzonisaid barrel support rearwardly of said stem and` engageable with said stem between the endsbf the latter, said stem being arranged to pivot about said fulcrum and withdraw. the bolt to retracted .position when the demounted barrel structure is lifted by said handle, said pivotal movement being caused by -the weight of theforward end of the barrel structure. i l' 1 VAL A. BROWNING. 

